gatekeeper (suicide prevention)
Specifically refers to a person trained to notice signs of suicidal ideation and intervene by talking and providing support. This is a specialized mental health term in Japan.
The municipality holds gatekeeper training courses for suicide prevention.
gatekeeper (media, networking)
General sense of a person or entity that controls access to something, such as information, opportunities, or resources. Used in contexts like journalism, business, and technology.
Editors serve as gatekeepers of information.